Physics Lectureship in Maynooth!

Posted in Maynooth with tags , , , , , on June 18, 2019 by telescoper

Every now and then I have the opportunity to use the medium of this blog to draw the attention of my vast readership (both of them) to employment opportunities. Today is another such occasion, so I am happy to point out that my colleagues in the Department of Experimental Physics are advertising a lectureship. For full details, see here, but I draw your attention in particular to this paragraph:

The Department of Experimental Physics is seeking candidates with the potential to build on the research strengths of the Department in the areas of either terahertz optics or atmospheric physics. The Department is especially interested in candidates with research experience that could broaden the scope of current research activity. This could include for example terahertz applications in space, imaging, remote sensing and communications or applications of atmospheric physics related to monitoring and modelling climate change. It would be an advantage if the candidate’s research involved international collaboration with the potential for interdisciplinary initiatives with other University institutes and departments.

The deadline for applications is Sunday 28 July 2019 at 11.30pm.

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Euclid Updates

Posted in The Universe and Stuff with tags , , , , on June 17, 2019 by telescoper

Following the Euclid Consortium Meeting in Helsinki a couple of weeks ago, here are a couple of updates.

First, here is the conference photograph so you can play Spot The Telescoper:

(The picture was taken from the roof of the Finlandia Hall, by the way, which accounts for the strange viewpoint.

The other update is that the European Space Agency has released a Press Release releasing information about the location on the sky of the planned Euclid Deep Fields. Here they are (marked in yellow):

These deep fields amount to only about 40 square degrees, a small fraction of the total sky coverage of Euclid (~15,000 square degrees), but the Euclid telescope will point at them multiple times in order to detect very faint distant galaxies at enormous look-back times to study galaxy evolution. It is expected that these fields will produce several hundred thousand galaxy images per square degree…

Selecting these fields was a difficult task because one has to avoid bright sources in both optical and infrared (such as stars and zodiacal emission) so as not to mess with Euclid’s very sensitive camera. Roberto Scaramella gave a talk at the Helsinki Meeting showing how hard it is to find fields that satisfy all the constraints. The problem is that there are just too many stars and other bits of rubbish in the sky getting in the way of the interesting stuff!

 

For much more detail see here.

 

Coloured Ball Illusion

Posted in Art on June 16, 2019 by telescoper

This image, created by David Novick, is the most impressive colour illusion I have ever seen: all the balls are actually the same colour, brown.

If you don’t believe me, zoom in on any one of them…

I don’t really know why this fascinating image causes the effect that it does, but think it is a combination of hardware and software issues! The hardware issues include the fact that colour receptors are not distributed uniformly at the back of the human eye, so colour perception is different when peripheral cues are present, and also that their spectal response is rather broad with considerable overlap between the three types of cell. The software issue is something to do with how the brain resolves a colour when there are other colour nearby:nNotice how the balls take on the colour of the lines passing across them..

A Ring of Controversy Around a Black Hole Photo

Posted in The Universe and Stuff on June 15, 2019 by telescoper

This is a long post but well worth reading if you want to know what we really know about the black hole in M87..

Of Particular Significance

It’s been a couple of months since the `photo’ (a false-color image created to show the intensity of radio waves, not visible light) of the black hole at the center of the galaxy M87, taken by the Event Horizon Telescope (EHT) collaboration, was made public. Before it was shown, I wrote an introductory post explaining what the ‘photo’ is and isn’t. There I cautioned readers that I thought it might be difficult to interpret the image, and controversies about it might erupt.EHTDiscoveryM87

So far, the claim that the image shows the vicinity of M87’s black hole (which I’ll call `M87bh’ for short) has not been challenged, and I’m not expecting it to be. But what and where exactly is the material that is emitting the radio waves and thus creating the glow in the image? And what exactly determines the size of the dark region at…

View original post 6,013 more words

The End of the Common Travel Area?

Posted in Biographical, Cardiff, Politics with tags , , on June 14, 2019 by telescoper

I’m back in Cardiff for a couple of days after flying from Dublin this morning.

When my flight arrived at Cardiff Airport there was yet again a full passport and immigration check on all passengers.

There is supposed to be a Common Travel Area including the UK and Ireland (as well as the Channel Islands and the Isle of Man), and passport checks are not supposed to be made routinely at borders within the CTA.

I have noticed passport checks happening at Cardiff Airport before (e.g. here and here) but I’ve previously imagined there was some specific reason for them. Passport checks have, however, been carried out every time I have arrived in Cardiff recently and it is now abundantly clear that there has been a material change of policy.

When I got to the desk and handed over my passport I asked the Officer whether these checks were being imposed all the time now. She said yes: there are now full passport and immigration checks on all flights to Cardiff from Dublin.

This is from the UK Government’s website:

Well, if they check all passengers on all flights then that sounds like ‘routine’ to me. In other words the British authorities are violating the Common Travel Area agreement just weeks after undertaking to uphold it.

Did someone say ‘Perfidious Albion’?

Special 1919 Eclipse Centenary Offer!

Posted in History with tags , on June 13, 2019 by telescoper

A little later than planned, a paper what I wrote for Contemporary Physics to commemorate the centenary of the 1919 Eclipse Expeditions has now appeared online. The print edition will be available in due course.

Here is the abstract:

Unfortunately the paper is behind a paywall, but as a special dispensation I am to offer FIFTY free downloads of the paper to friends, colleagues and random people on the internet.

If you’d like to download a FREE copy of the PDF of the paper A revolution in science: the eclipse expeditions of 1919 then you may do so by clicking this link. How’s that for clickbait?

UPDATE: the free copies have now all gone so I removed the link.

To be honest I’m not sure what stops you sending the PDF to anyone else, but apparently those are the rules…

Astronomy Bookalike

Posted in Astronomy Lookalikes on June 13, 2019 by telescoper

It has been pointed out to me that I haven’t contributed anything to my collection of Astronomy Lookalikes recently. My only excuse is that I haven’t really thought of any. I’ll try to get it going again. Suggestions are always welcome.

In the meantime take a look at this book look-alike:

If you click on the picture you can make it bigger.

These two pages are taken from two different books on Astrophysics written about a decade apart by two different authors. This is by no means the only point of similarity between these particular volumes. I wonder if by any chance they might be related?

I couldn’t possibly comment.